You don't need A-Levels or a degree to be a pilot.
But if you want to keep up with the competition that will most definitely be around you when you're doing groundschool, and indeed applying for the airline jobs - a decent educational background is an absolute must.
I've just finished groundschool at OAT. Purely, as an indication of the type of competition I might be up against, there are only 3 people without a degree and only 1 without A-Levels (out of 20 people)
So it stands to reason that if you're all reasonably bright people and you all do your flying training to a similar standard, how does an airline start the sifting process? I think it's rather obvious.
It is becoming more and more common, if not already the "standard", that a minimum of 2-A Levels and a degree is a basic requirement for any would-be pilot looking to secure a position in today's market.
Sure, they'll be plenty of folk that get their airline job without a degree and indeed probably without A-Levels but realistically, a young person, looking at what they should do at the age of 17/18 seriously needs to consider going to college, getting some A-Levels, then going to University, doing a degree they enjoy, learning a few life skills, maturing a bit - and then start looking at the flying career.